1. Field of the Invention
The present invention relates to a wire waterproofing method and a wire having a waterproof part formed by the waterproofing method and is particularly designed to be able to apply a waterproof treatment at an arbitrary position of a wire arranged in a water susceptible area of a vehicle.
2. Description of the Related Art
Conventionally, if a wiring harness is arranged along a water susceptible area of a vehicle such as a car or a motorcycle, a ground terminal is crimped and connected to an end of a ground wire of the wiring harness and grounded by being bolted to a vehicle body in many cases. In this case, if the fixed position of the ground terminal is located in a water susceptible area, water enters the inside of the ground wire through an exposed core section crimped and connected to the ground terminal and penetrates to the other end of the ground terminal through clearances of a core made up of a multitude of strands and covered by an insulating coating layer. In this case, a terminal connected to the other end of the ground wire is often inserted and locked in a connector and the penetrating water also enters the connector at the other end of the ground wire, which causes a problem of corroding the terminal in the connector.
For the above problem, various ground wire waterproof treatments have been conventionally proposed.
For example, the present applicant proposed to drop a waterproofing agent between an insulating coating barrel 2a and a core barrel 2b of a ground terminal 2 crimped and connected to an end of a ground wire 1 as shown in FIG. 11 of Japanese Unexamined Patent Publication No. 2006-228709, and air inside an insulating coating layer is sucked from the other end of the ground wire 1 to reduce pressure. In this way, the dropped waterproofing agent 3 is infiltrated into the inside of the insulating coating layer to fill clearances of a core made up of a plurality of strands, thereby preventing water penetration from a connecting portion with the ground wire 2 into the inside of the ground wire 1.
Also in Japanese Unexamined Patent Publication No. 2007-13405, a waterproofing agent is dropped to a ground terminal at an end of a ground wire and air inside the ground wire is sucked to infiltrate the waterproofing agent into the inside of the ground wire by a similar method. In JP 2007-13405, a leakage preventing wall 4b is arranged between both side walls 4a of a jig 4 and the waterproofing agent 3 is dropped with the leakage preventing walls 4b held in close contact with opposite side surfaces of the ground terminal 2 as shown in FIG. 12 in order to position the ground terminal 2 and prevent the lateral leakage of the waterproofing agent.
As described above, in each of the waterproofing methods of JP 2006-228709 and JP 2007-13405, the waterproofing agent is dropped to the exposed core section of the ground terminal at the end of the ground wire and a waterproofed position by the waterproofing agent is located at the ground terminal at the end of the ground wire. In other words, it is supposed that the ground terminal is crimped and connected to the end of the ground wire and the ground terminal is bolted to a body panel. In order to apply a waterproof treatment to the ground wire in this way, the ground terminal to be fixed to the vehicle needs to be crimped and connected to the end of the ground wire and, depending on vehicles, it is difficult in some cases to ensure a place where the ground terminal is fixed. In such a case, the ground wire has to be extended up to the place where the ground terminal can be fixed and unnecessary handling of the ground wire is required. In addition, if the ground wire is unnecessarily made longer, a possibility of the ground wire being interfered with and damaged by an external interfering member is increased by that much. Even if a waterproof treatment is applied at an end position connected with the ground terminal, water may enter at a damaged position and penetrate to a connector connecting portion at the other end of the ground wire if the ground wire is damaged at an intermediate position.
Further, the jig for positioning the ground terminal and preventing the leakage of the dropped waterproofing agent is necessary at the time of dropping the waterproofing agent to the ground terminal as disclosed in JP 2007-134054. Since this jig needs to be provided for each size of ground terminals, equipment cost increases, which leads to an increase of production cost. In view of these points, there is a room for improvement.
In view of the above problems, an object of the present invention is to reliably prevent water penetration into a connector connecting portion by applying a waterproof treatment not at a fixed position of a ground terminal to be bolted to a vehicle body, but at an arbitrary position of a wire to be arranged in a water susceptible area, thereby enabling the waterproof treatment to be applied at as close a position as possible to the wire connected to a connector without using a jig.